High
Connection on Vaillant ecoTEC plus Regular

Your boiler's main internal computer and the front control panel have lost their connection, meaning the unit cannot receive instructions or show you what is happening.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

NocommunicationbetweenthePCB andtheuserinterface | Electronicsdefective

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus Regular installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.70View →

All 81 fault codes on the ecoTEC plus Regular

Seeing a different code? Every code this model can display, in one place.

3596conD,11d.02D.4d.11F.00F.01F.10F.11F.13F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.83F.85F.87F.88F.89F22F70P.01S.0S.01S.02S.2S.03S.04S.05S.06S.07S.7S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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